A boat is marooned at what used to be Lake Mead Marina in Nevada. If the level of the reservoir continues to drop, Las Vegas may lose 40 percent of its water by 2012.

Written by

JOHN LIPPERT and JIM EFSTATHIOU JR.
Bloomberg News

On a cloudless December day in the Nevada desert, workers in white hard hats descend into a 30-foot-wide shaft next to Lake Mead. They'll dig down into the limestone surrounding the reservoir that supplies 90 percent of Las Vegas' water. In September, when they hit 600 feet, they'll turn and burrow for three miles, laying a new pipe as they go.

The crew is in a hurry. They're battling the worst 10-year drought in recorded history along the Colorado River, which feeds the 110-mile-long reservoir. Since 1999, Lake Mead has dropped about 1 percent a year. By 2012, the lake's surface could fall below ...